Atomizers have long been in use for air humidification, in particular of interior spaces. Such atomizers make use of ultrasound or fine nozzles in order to generate a cold fog composed of tiny droplets. The known atomizers have the following disadvantages in principle. Lime that is dissolved in the water being used is atomized along with the water and perceived later in the environment as undesired fine lime precipitation. Furthermore, in the case of air humidifiers with two containers that are flowed through in series, there is a risk of germs building up at high temperatures and/or during standstill times. This, too, is also not effectively countered by measures that are taken in the first container against the build up of germs. Thus, particularly given long standstill times, germs form in the second, downstream container and are then immediately atomized as well when the air humidifier is switched on. Finally, the lime dissolved in the water leads not only to the described lime deposits in the environment of the air humidifier, but also impairs the service life and/or functioning of the oscillating plate used in the case of ultrasonic atomization, or of the nozzle used in the case of nozzle atomization. The functioning of the oscillating plate is impaired by lime deposits, in particular. These lime deposits can be removed by a cleaning process that takes place every three to four days. However, in the case of mechanical cleaning there is the risk of damaging the oscillating plate. The atomizing function of the nozzle is influenced, in particular, by an increasing obstruction due to lime deposits. In the known apparatuses, use is made of deliming cartridges in order to reduce these liming problems. However, said cartridges must be frequently changed and, in accordance with new findings, form an optimum feeding ground for bacteria and fungi owing to the large surface of the granulate used.
JP 10-281502 A1 discloses an air humidifier that comprises a first container and a second container that can be filled from the first container, an atomizer and electrodes arranged in the first container. This air humidifier has the above-described problems associated with the lime and the hygiene in the second container.